B. ne chemical reaction involved in burning wood
c. less energy is released than is used by the reaction
3. why is a spark of energy required to begin the chemical reaction of
burning a fossil fuel? what is another name for this spark of energy?
4. the reaction below is an exothermic reaction
k2o (s) co2 (g) k2co3 (s)
a. rewrite this reaction and add "t energy" in the correct location.
b. describe how the energy level of the reactants compares to the energy
level of the products.
5. the reaction below is an endothermic reaction.
2hgo (s) 2hg +o2 (g)
a. rewrite this reaction and add energy" in the correct location
b. describe how the energy level of the reactants comporon to th

The transfer of heat through the movement of a gas or liquid a. convection b. conduction c. radiation

1. how much energy is needed to raise the temperature of 40.0 g of argon from 25c to 40c? the specific heat capacity of argon is 0.520 j/(g·k) 2a. 23.0 ml of 0.100 m hcl (standard) are added from a buret to neutralize 50.0 ml of an unknown basic solution. 2b. if the oh- produced in the previous reaction came from ca(oh)2, then what is the molarity of the ca(oh)2? 3.calculate the new freezing-point of a solution when 60.5 grams of cacl2 solute is dissolved in 0.612 kg of water. 4. what is the maximum number of moles of alcl3 that can be produced from 5.0 mol al and 6.0 mol cl2? 5. a sample of oxygen gas has a volume of 150 ml when its pressure is 0.923 atm. if the pressure is increased to 0.987 atm and the temperature remains constant, what will the new volume be? 6. nitrogen gas in a closed container at a temperature of 100.0 oc and 3.0 atm is heated to 300 oc. what is the pressure of the gas at the higher temperature?

Consider an insulating crystal, made up of layers of atoms. what form would you expect the temperature dependence of the phonon heat capacity to approach at extremely low temperatures if the interlayer coupling is i)very strong (rigid coupling), and ii) very weak. explain.